The animal core will facilitate all aspects of the mouse studies proposed in this program project. This includes management of; 1) mouse strains to be used for genetic/microarray dissection of strain-specific responses to nicotine, 2) animal husbandry of genetically modified animals through homologous recombination, 3) genotyping of mouse strains and the generated backcrosses, 4) animals for immunohistochemical and protein chemistry studies, 5) timed-pregnant strains for tissue culture applications, 6) animals for peripheral immune cell function studies and 7) animals pertaining to inflammation and COPD modeling. This animal core therefore provides a central shared facility allowing for the coordinated use of animals for Project 2 (Drs. Rogers and Capecchi) and Project 3 (Drs. Hoidal and Gahring). This core will maintain barrier-sustained, disease-free colonies of conventional and neurologically and peripherally modeled mice. Further, this core will implement and maintain nicotine treatment of mice (oral administration in drinking water as well as the smoke inhalation model, 7 days per week) for Projects 2 and 3. Mouse colonies are presently housed in the University of Utah School of Medicine Animal Resource Center (ARC) facility that is free of infectious agents and constructed to support new barrier housing areas that operate with regulated environmental conditions. A second IACUC accredited mouse facility at the Veterans Administration research facility presently houses the smoking chamber that is used for inhalation studies. The housing and treatment of all mice by this core assures minimal experimental variability between projects. All animals will be uniquely identified including the use of implanted electronic chip identification transponder chips where applicable. Animal databases will be networked to all investigators and will be accessible between Projects to assure maximum utilization of animals and this resource.